CVE-2026-56818
Published:August 07, 2026
Updated:September 01, 2026
Netty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, the RedisArrayAggregator Redis codec clears retained partial aggregate state when the maxNestedArrayDepth limit is exceeded, but it does not clear the same state when the sibling maxElements limit is exceeded. A peer can start a valid RESP array, send a bulk string child, then send a nested array header longer than the configured maxElements. Netty throws a decoder exception in decodeRedisArrayHeader, but the existing partial aggregate remains retained in the handler. If the application leaves the channel alive after the exception, later messages are still consumed into the pre-error aggregate, allowing an unauthenticated peer to keep attacker-controlled aggregate state alive across a security-limit exception and pin retained pooled buffers. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.
Affected Packages
https://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-4.2.0.Final <netty-4.2.16.FinalFix Suggestion:
Update to version netty-4.2.16.Finalhttps://github.com/netty/netty.git (GITHUB):
Affected version(s) >=netty-4.1.0.Final <netty-4.1.136.FinalFix Suggestion:
Update to version netty-4.1.136.Finalio.netty:netty-codec-redis (JAVA):
Affected version(s) >=4.1.0.Final <4.1.136.FinalFix Suggestion:
Update to version 4.1.136.Finalio.netty:netty-codec-redis (JAVA):
Affected version(s) >=4.2.0.Final <4.2.16.FinalFix Suggestion:
Update to version 4.2.16.Finalio.netty:netty-codec-redis (JAVA):
Affected version(s) >=4.2.0.Final <4.2.16.FinalFix Suggestion:
Update to version 4.2.16.Finalio.netty:netty-codec-redis (JAVA):
Affected version(s) >=4.1.0.Final <4.1.136.FinalFix Suggestion:
Update to version 4.1.136.FinalRelated Resources (7)
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Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW
Weakness Type (CWE)
EPSS
Base Score:
0.28